What is facebookexternalhit? AI crawler guide
facebookexternalhit is a crawler or fetcher associated with Meta. See source-graded user-agent, robots.txt, verification, and observation guidance.
What is facebookexternalhit?
facebookexternalhit is a documented Meta crawler or fetcher. Meta link preview crawler used when content is shared on Meta family apps.
Evidence status
| Field | Value |
|---|---|
| Evidence | Officially documented |
| Lifecycle | Active |
| Purpose | social |
| robots.txt posture | partial |
| Source checked | 2026-06-11 |
Documented user-agent
facebookexternalhit
Allowing facebookexternalhit creates the possibility of retrieval. To find out whether Meta AI actually cites or recommends you, track your Meta AI mentions over time.
robots.txt allow example
User-agent: facebookexternalhit Allow: /
robots.txt block example
User-agent: facebookexternalhit Disallow: /
What the rule can and cannot do
Robots.txt expresses an access policy to compliant automated crawlers. It does not authenticate the sender, remove content already collected, or guarantee that a model will use or not use content.
How to verify a request
- Match the complete documented user-agent where one exists. A match is only a clue.
- Look for operator-published IP ranges, reverse DNS, or signed-request guidance. None is attached to this record.
- Keep the observed request, operator documentation, and any inference as separate fields.
JavaScript behavior
The cited operator material does not verify JavaScript rendering. Serve useful HTML before client-side JavaScript where possible.
Related bots
- FacebookBot: Another Meta social crawler to compare.
- TikTokSpider: Also tracked as a social crawler.
- Meta-WebIndexer: Also operated by Meta.
- GPTBot: Shares crawler-policy context with facebookexternalhit.
- meta-externalads: Also operated by Meta.
- Meta-ExternalAgent: Also operated by Meta.
- AI2Bot: Shares crawler-policy context with facebookexternalhit.
- Applebot: Shares crawler-policy context with facebookexternalhit.
- atlassian-bot: Shares crawler-policy context with facebookexternalhit.
- Meta AI: facebookexternalhit connects this operator term to its crawler behavior.
- AI Training Opt-Out: facebookexternalhit gives crawler context for AI Training Opt-Out.
Frequently Asked Questions
What is facebookexternalhit?
facebookexternalhit is a officially documented crawler or fetcher record associated with Meta.
What user-agent does facebookexternalhit use?
facebookexternalhit. Check the evidence status before attributing a matching request.
Can facebookexternalhit be blocked in robots.txt?
The record identifies facebookexternalhit as the token to review. Robots.txt is a request policy, not proof of model use or non-use.
How can I verify a facebookexternalhit request?
Treat the user-agent as a clue and look for operator-published IP, reverse-DNS, or signature guidance.
Data & Sources
- Meta documentation - Primary source for facebookexternalhit crawler details.